Dissertations / Theses on the topic 'Copper isotope'
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Maher, Kierran C. "Analysis of copper isotope ratios by multi-collector inductively coupled plasma mass spectrometry and interpretation of copper isotope ratios from copper mineralization." Online access for everyone, 2005. http://www.dissertations.wsu.edu/Dissertations/Summer2005/k%5Fmaher%5F072705.pdf.
Full textBabcsanyi, Izabella. "Copper transport and isotope fractionation in an agrosystem." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAH006/document.
Full textSince the end of the 19th century, the use of copper (Cu)-based fungicides has resulted in increased Cu concentrations in vineyard soils, but also in downstream aquatic ecosystems. The aim of the thesis was to better understand the fate of this Cu in an agrosystem based on assessing Cu isotope fractionation (65Cu/63Cu). The results have shown that the surface vineyard soils have become enriched in Cu from 9 to 28 times compared to the background level during 4 to 5 decades of vine-growing and that clay minerals were the major Cu sorbing phases in the soils. During rainfall, runoff mobilized ~1% of the applied Cu during the, mainly associated with clays. The stormwater wetland collecting the runoff retained in average 68% of the dissolved and more than 92% of particulate Cu. Cu isotope ratios measured in the wetland suggested dissolved Cu sorption to the sediments and in situ reduction of Cu(II) due to biogeochemical processes
FAQUIM, ELAINE de S. "Estudo da determinacao de cobre por analise por diluicao isotopica subestequiometrica." reponame:Repositório Institucional do IPEN, 1994. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10397.
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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
Young, Steven E. "Crystal chemical control on intra-structural copper isotope fractionation in natural copper-iron-sulfur minerals." Diss., The University of Arizona, 2003. http://hdl.handle.net/10150/289914.
Full textMaynard, Annastacia Lin. "Copper isotope compositions of Cenozoic mafic-intermediate rocks of the Northern Great Basin and Snake River plain (USA)." Thesis, Kansas State University, 2016. http://hdl.handle.net/2097/32881.
Full textDepartment of Geology
Matthew E. Brueseke
Mid-Miocene epithermal Au-Ag ores of the northern Great Basin USA are related to magmatism associated with the inception of the Yellowstone hotspot. The geochemical chemical connection between these ores and spatially and temporally related volcanism is not well understood, but has been suggested (Kamenov, 2007; Saunders et al., 2015). These Cu- and Pb- isotope studies show that the ore and associated gangue minerals have different sources of Pb, which supports evidence that the metal(loids) originate from a deep magmatic source (Saunders et al., 2008). Cu isotopes as a tool for exploring linkages between ore deposits and related volcanic rocks is a new and evolving field. A suite of mid-Miocene Northern Great Basin (NGB) and Snake River Plain (SRP) volcanic rocks was analyzed by aquaregia leach for their δ⁶⁵Cu compositions. These samples have all been previously characterized and include basalts, trachybasalt, basaltic andesites, and basaltic trachyandesites that are representative of regional flood basalt magmatism and younger basalt eruptions in central Idaho. Included are rocks from the Santa Rosa-Calico volcanic field, NV (e.g., Buckskin-National district); Owyhee Mountains, ID (Silver City District); Midas, NV region, near Jarbidge, NV; and a locality proximal to Steens Mountain, OR. Also included are two Pleistocene basalts from the central Snake River plain unequivocally related to the Yellowstone hotspot volcanism (McKinney Basalt and Basalt of Flat Top Butte), and one Eocene basalt from the Owyhee Mountains that is related to pre-hotspot arc volcanism. International rock standards ranging from ultramafic to intermediate were also analyzed in this study for comparison. Our new δ⁶⁵Cu data greatly expands the range of known Cu isotopic compositions for basalts, with values ranging from -0.84‰ to +2.61‰. These values overlap with the δ⁶⁵Cu of regional ores, further suggesting a link between the source(s) of the ores and the NGB rocks. The range of δ⁶⁵Cu values also overlaps with mantle rock values, suggesting that the Cu isotopic composition may be a signature derived from the mantle source. Fractionation mechanisms that cause such a broad range in Cu isotopes are still unclear but liquid-vapor transitions and mantle metasomatism are being explored. Furthermore, δ⁶⁵Cu values of international rock standards reported in this study did not agree with previously reported data (Archer and Vance, 2004; Bigalke et al., 2010; Moeller et al., 2012; Liu et al., 2014, 2015) suggesting that aquaregia leach may not be a preferable technique when analyzing volcanic rocks.
Peel, Kate Elizabeth. "Studies into the Stable Isotope Geochemistry of Copper and Zinc in Aquatic Systems." Thesis, Imperial College London, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.503795.
Full textFernandez, Alvaro. "Moving from rocks to hydrologic systems are Cu, Fe, and Zn isotopes fractionated during weathering? /." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
Full textGiunti, I. "Geochemical and isotopic tracers in copper deposits and ancient artifacts: a database for provenance." Doctoral thesis, Università degli studi di Padova, 2011. http://hdl.handle.net/11577/3421614.
Full textLa provenienza di manufatti metallici nella prima storia della metallurgia è stata il maggiore problema in archeologia per molte decadi. I rapporti isotopici del Pb (206Pb/204Pb, 207Pb/204Pb, 208Pb/204Pb) sono comunemente usati per definire la provenienza dei manufatti in archeometria, ma le interpretazioni sono fortemente dibattute e qualche volta ambigue dal momento che i depositi naturali mostrano di frequente composizioni isotopiche del Pb sovrapposte. Il primo modo di ridurre le sovrapposizioni osservate è di aumentare la precisione analitica. Il secondo modo di ridurre le ambiguità è di combinare la segnatura isotopica del piombo con altri indicatori geochimici, ad esempio con altri dati isotopici o di elementi minori e in traccia. L’estrazione di un’informazione di provenienza affidabile dalla combinazione di numerosi traccianti geochimici, tuttavia, richiede analisi statistiche sofisticate. Qui più di 350 campioni sono stati raccolti da 50 aree minerarie. Alcuni dei più importanti distretti di rame nella porzione centro-orientale delle Alpi meridionali (Alpi Carniche, copertura Permo-Triassica e basamento Varisico), nelle Alpi occidentali (Zona Pedemontana, Brianzonese Ligure, nappe del Gran Paradiso, Argentera), negli Appennini Liguri (Libiola, Monte Loreto) e nella Toscana meridionale (Isola d’Elba, “Colline metallifere” and Montecatini Val di Cecina). Sono stati analizzati circa 270 campioni di minerali grezzi primari (rame, solfuri di rame-ferro e solfo-sali di rame) e secondari (carbonati e ossidi di rame supergenico e rame nativo) e ritrovati archeologici (scorie, manufatti di rame e bronzo di età da Calcolitica a Tardo Bronzo) per analisi degli isotopi del piombo e degli minori e in tracce (inclusi la maggior parte dei metalli di transizione, elementi calcofili e terre rare). Inoltre è stata testata la fattibilità di misure di routine del rapporto isotopico del Cu (65Cu/63Cu) e del suo possibile uso come tracciante delle miniere. E’ stata eseguita un’avanzata analisi statistica (PCA, PLS-DA, NPC) su un database per ottenere strumenti statistici discriminanti per la provenienza dei metalli. I campioni sono stati prima caratterizzati mineralogicamente e petrologicamente (XRD e RL-OM) e successivamente analizzati mediante tecnica ICP-QMS (Spettrometri di Massa Quadrupolare mediante Plasma accoppiato induttivamente) per gli elementi in tracce e i rapporto isotopico 65Cu/63Cu. E’ stata usata la spettrometria di massa multicolletore (MC-ICP-MS) per la determinazione precisa dei rapporti isotopici del piombo (206Pb/204Pb, 207Pb/204Pb, 208Pb/204Pb). L’insieme di dati chimico/isotopico delle miniere è stato analizzato con l’Analisi delle Componenti Principali (PCA) e con l’Analisi Discriminante dei minimi quadrati parziali (PLS-DA). I dati chimici e isotopici sono stati inseriti in una matrice bidimensionale caratterizzata dai campioni (manufatti) nelle righe della matrice e le analisi chimiche come variabili nelle colonne. L’insieme dei dati è stato inoltre analizzato con il test della Combinazione non-parametrica (NPC), che è un metodo non-parametrico multivariato inferenziale che libera dalle stringenti assunzioni dei metodi parametrici (come il t e F test) e permette un’analisi più flessibile sia in termini della specificazione di ipotesi multivariate, sia in termini della natura della variabili in causa. Uno dei più importanti vantaggi dell’applicare statistiche non-parametriche come i test di permutazione, è che permette di lasciare libera l’assunzione di normalità delle variabili di risposta. Inoltre, il Test NPC non richiede la modellazione della dipendenza tra le variabili e non è affetta da problemi di perdita di gradi di libertà quando il numero di variabili è grande comparato al numero dei campioni. I risultati dell’analisi del Test NPC sono stati ottenuti usando il programma libero NPC Test R10, dove abbiamo usato l’F-test come test statistico e la funzione di combinazione Fisher come funzione combinante. I risultati possono essere rappresentati graficamente mediante la PCA. La disponibilità di una comprensiva e senza precedenti quantità di dati geochimici per i depositi Alpine di rame ha dato informazioni rilevanti per la loro interpretazione metallo genica. In particolare, le composizioni isotopiche delle tracce di piombo nelle mineralizzazione a rame in depositi di solfuri idrotermali della regione sudalpina centro-orientale sono state combinate con i dati degli isotopi del piombo di depositi poli-metallici idrotermali esistenti nella stessa area, e comparati con le composizioni isotopiche di potenziali sorgenti di piombo. Depositi stratiformi di rame e poli-metallici pre-Varisici (tardo Ordoviciano - primo Siluriano), depositi a vene post-Varisiche (da Permiano a Triassico) e depositi a stratabound ospitati in sedimenti (da Permiano al primo Triassico) sono caratterizzati da rapporti altamente variabili di piombo radiogenico e non, ma mostrano valori di (= 238U/204Pb) e W (= 232Th/204Pb) molto simili e alti. Si osserva un relativo progressivo aumento in piombo radiogenico dai (i) depositi pre-Varisici alle (ii) vene ricche di solfuri post-Varisiche presenti nel basamento metamorfico Varisico e nelle unità inferiori-intermedie della sequenza vulcanica per primo Permiano alle (iii) vene post-Varisiche ricche in fluorite e solfuri nelle unità superiori della sequenza vulcanica del primo Permiano alla (iv) vene post-Varisiche ricche in fluorite che tagliano i sovrastanti sedimenti tardo-permiani e i dicchi mafici medio-triassici. Le sorgenti di piombo dominanti per tutti questi depositi sono i (meta)sedimenti del Cambriano-Devoniano del basamento Varisico. Contributi da rocce ignee permiane e triassiche sono di minore importanza, se presenti, anche per depositi di vena che sono evidentemente correlati con il magmatismo permiano. Mentre l’impronta isotopica del Pb potrebbe potenzialmente aiutare la probabile provenienza del manufatto archeologico, ci sono numerose difficoltà correlate. Prima di tutto, i depositi naturali hanno frequentemente composizioni isotopiche del Pb sovrapposte. Così in aggiunta agli isotopi del Pb sono stati analizzati gli elementi in tracce, terre rare e rapporti isotopici del rame (65Cu/63Cu). Il rapporto isotopico del rame 65Cu/63Cu è sensibile alla temperature di segregazione del minerale; quindi fornisce informazioni sulla natura del minerale usato per la produzione del manufatto. E’ stata operato una selezione statistica per identificare le variabili che più effettivamente distinguono le miniere investigate. Questo è stato raggiunto usando una strategia PLS-DA. Questa tecnica è un metodo di classificazione che modella le differenze tra due classi. Il metodo PLS calcola un modello di regressione lineare tra la matrice dei predittori (X) e il vettore risposta (Y): in questo particolare caso il vettore Y è espresso con un codice binario. Il modello restituisce scores and loading plots così come il coefficiente di regressione per ogni variabile. Viene inoltre fornito una stima del significanza statistica di questo coefficienti di regressione. La rilevanza statistica delle variabili è stata testata attraverso il Martens Uncertainty test. Lo studio delle matrici di correlazione e dei coefficienti del modello permette di definire un sotto-insieme di variabili in grado di discriminare i campioni provenienti dalla differenti aree/siti. Un singolo modello non è stato sufficiente ed è stata richiesta una strategia di esclusione a più passaggi per ottenere una discriminazione soddisfacente. La procedura adottata può essere schematizzata come segue: 1) l’intero insieme di dati è preso in considerazione e viene creato un modello PCA. Attraverso lo studio dei score plots generato dalla combinazione delle prime componenti principali (in genere da PC1 a PC4) la località maggiormente discriminante viene scelta per il processo di esclusione; 2) il passo successivo la selezione della variabile con l’intento di enfatizzare le differenza tra la località selezionata e tutte le altre località: l’obiettivo è costruire un semplice modello discriminante usando solo PC1 o non più di due PCs: 3) i dati correlati alla località selezionata sono esclusi dalla matrice originale e l’intero processo è quindi ripetuto su questa matrice ridotta inizialmente considerando di nuovo tutte le variabili. Il potere discriminante del database è stato testato sulla provenienza di metalli e scorie di rame provenienti dall’area di Agordo (Belluno) e di frammenti e scorie di rame preistorici provenienti da Millan (Bressanone, Bolzano). I campioni sono stati proiettati in un modello PCA esistente, e la loro posizione comparata con la posizione dei campioni usati per costruire il modello. Lo stesso metodo di proiezione è stato inoltre usato per la validazione della strategia di esclusione a passaggi multipli. I dati per manufatti e scorie di rame proveniente dall’area di Agordo mostrano che il modello discriminante che meglio identifica le miniere di Agordo è perfettamente applicabile ai manufatti, indicando chiaramente che il metallo è stato estratto dalle miniere locali. Per il caso di Millan, il modello discriminante dei depositi che meglio descrive il frammento di rame è quello che identifica l’area della Val Venosta (miniere di Oris, Val Martello e dello Stelvio), localizzate 80 km a ovest del sito archeometallurgico di Millan. Questo risultato suggerisce che il campione di rame è geneticamente non correlato alla grande quantità di scorie associate prodotte durante il processo di smelting del rame provenienti dalle locali miniere di calcopirite ricche di sfalerite e galena, che hanno un carattere mineralogico e geochimico significativamente differente. E’ presentata una strategia vincente per caratterizzare miniere di rame e per tracciare la provenienza di minerali e antichi manufatti di rame. E’ stato sviluppato un intero protocollo di controllo, che parte dal campionamento all’analisi quantitativa, per assicurare una corrispondenza geologica e una buona qualità dei dati analitici. Le misure di un vasto numero di elementi che include le terre rare (REE) insieme con i rapporti isotopici del rame e del piombo in minerali di rame ha permesso una completa caratterizzazione geochimica delle miniere a rame investigate. I dati raccolti sono stati usati per costruire un database che può essere usato come riferimento fondamentale per tracciare l’estrazione del metallo e la sua diffusione in passato. L’applicazione di avanzate tecniche statistiche ai dati geochimici e isotopici fornisce uno strumento potente per discriminare le aree delle miniere sorgenti. Le applicazioni presentate relativamente ai campioni e scorie di rame sembrano confermare che le analisi possono essere operate con successo su campioni archeometallurgici. La disponibilità di un tale ammontare di dati esaustivo e senza precedenti per i depositi di rame alpini inoltre da informazioni interessanti per la loro interpretazione geochimica e metallogenica. In particolare, gli alti valori di e W dei depositi del sud-alpino centro-orientale sono consistenti con andamenti isotopici regionali dei depositi a Pb-Zn in settori più settentrionali e orientali delle Alpi orientali (Australoalpino, Sudalpino orientale) e di numerosi depositi metallici e a Pb-Zn dell’area mediterranea di età paleozoica fino a triassica (Sardegna, Cordigliera Betica) o derivati da rimobilizzazione di depositi paleozoici (Toscana). Questa uniformità isotopica suggerisce l’esistenza di una provincia isotopica caratterizzata da una preponderanza di vecchio materiale sorgente detritico (primo Proterozoico fino ad Archeano), che si estende attraverso una relativamente estesa porzione di un più recente margine nord-Gondwaniano.
Rodríguez, Nathalie Pérez. "Biotic and abiotic isotope fractionation of copper and iron : From the lab to the field scale." Doctoral thesis, Luleå tekniska universitet, Geovetenskap och miljöteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26743.
Full textGodkänd; 2013; 20131028 (natper); Dissertation to be held in public in room E632 on Tuesday 17th of December at 10:00 am. External examiner: Dr. Dominik Weiss, Department for Earth Sciences and Engineering, Imperial College London. Chairman: Professor Björn Öhlander, Division of Geosciences and Environmental Engineering, Luleå University of Technology. --- Tillkännagivande disputation 2013-11-22 Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Nathalie Pérez Rodríguez Ämne: Tillämpad geologi/Applied Geology Avhandling: Biotic and Abiotic Isotope Fractionation of Copper and Iron. From the Lab to the Field Scale Opponent: Dr Dominik Weiss, Reader, Department of Earth Science & Engineering, Imperial College of London, UK Ordförande: Professor Björn Öhlander, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet Tid: Tisdag den 17 december 2013, kl 10.00 Plats: E632, Luleå tekniska universitet
Koenig, Karen Marie. "True absorption of selenium in dairy cows : stable isotope tracer methodology and effect of dietary copper." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/27972.
Full textLand and Food Systems, Faculty of
Graduate
Calkins, Brad Thomas 1953. "Petrographic, geochemical, X-ray, and stable isotope studies at the Morenci porphyry copper deposit, Greenlee County, Arizona." Thesis, The University of Arizona, 1997. http://hdl.handle.net/10150/278615.
Full textPenhall, John Lachlan. "A fluid inclusion and sulphur isotope study of epigenetic copper mineralisation in the Bimbowrie area, Olary Domain, South Australia /." Title page, contents and abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09SB/09sbp399.pdf.
Full textMohammed, Hiyam A. "Petrography, mineral chemistry, geochemistry and sulphur isotope studies of the Abhainn Strathain copper mineralisation, Meall Mór, South Knapdale, Scotland." Thesis, University of Strathclyde, 1987. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21494.
Full textGiblin, Julia Irene. "Isotope Analysis on the Great Hungarian Plain: An Exploration of Mobility and Subsistence Strategies from the Neolithic to the Copper Age." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1306863726.
Full textWalli, Adam. "Biomimetic Copper(I)-Mediated Activation of Dioxygen and Redox Non-Innocence in Copper(II) Complexes of Bis(oxazoline)s." Doctoral thesis, Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2014. http://hdl.handle.net/11858/00-1735-0000-0023-9636-9.
Full textCanovaro, Caterina. "DIFFUSION OF ALPINE COPPER IN FRIULI VENEZIA GIULIA IN THE MIDDLE-LATE BRONZE AGE." Doctoral thesis, Università degli studi di Padova, 2016. http://hdl.handle.net/11577/3424443.
Full textFin dalle prime fasi della ricerca archeometallurgica, un obiettivo importante è stato quello di determinare l'origine geologica del metallo impiegato per la produzione di manufatti, con l'intento di ricostruire i rapporti commerciali e il circuito di circolazione degli oggetti. Recentemente, diversi gruppi di ricerca hanno fatto ricorso, oltre alle tradizionali analisi chimiche e metallografiche, anche alle analisi dei rapporti isotopici del piombo per determinare il più accuratamente possibile la provenienza del metallo. Fin dall'inizio del 19° secolo il Friuli Venezia Giulia ha suscitato un profondo interesse, ma non è mai stato intrapreso un programma di ricerca sistematico in grado di definire i percorsi di circolazione del rame alpino nell’Italia Nord-Orientale. Infatti, solo sporadiche analisi chimiche sono state eseguite su alcuni lingotti ritrovati in Friuli e, fino ad ora, la loro interpretazione in termini di provenienza del metallo non è supportata da alcun dato isotopico. In questa cornice, lo studio archeometrico di manufatti di rame e bronzo provenienti da vari rispostigli protostorici ben datati del Friuli Venezia Giulia ha permesso di indagare l'origine del metallo utilizzato, individuando le aree sfruttamento dei minerali e, di conseguenza, di ricostruirne la circolazione nell’Italia Nord-orientale nella tarda Età del Bronzo. La scelta del Friuli come regione di interesse è dovuta al suo ruolo chiave come centro economico e commerciale tra l'area adriatica e l'Europa Centrale; pertanto, per delineare il ruolo di questa regione si è reso necessario lo studio di complessi ben sigillati che abbracciassero un range cronologico dal Bronzo Recente (BR) al Bronzo Finale (BF). A questo proposito, i depositi di Cervignano, Muscoli, Castions di Strada, Celò, Verzegnis, Galleriano e Porpetto, in cui sono contenuti sia lingotti che manufatti, sono stati individuati e selezionati in collaborazione con la Soprintendenza per i Beni Archeologici del Friuli Venezia Giulia. Non ci sono ripostigli noti per il Bronzo Medio (BM) e, quindi, due ritrovamenti sporadici - una spada da Belvedere e una da Canale Anfora - sono stati selezionati con l’intento di aumentare il numero di campioni rappresentativi di questo periodo. Nel presente lavoro è stato applicato un approccio multianalitico. Particolare rilevanza è stata attribuita allo studio della composizione chimica (elementi maggiori, minori e in traccia) e all'osservazione di eventuali fasi residue dovute a un raffinamento incompleto della materia prima; tali informazioni possono far luce sul tipo di carica minerale impiegata e sulla tecnologia del processo di fusione, tuttavia sono insufficienti per identificare sicuramente l'area sfruttamento del metallo. Per questo motivo, tali metodi di indagine sono stati accoppiati con l’analisi degli isotopi del piombo ed effettuati su una selezione di campioni considerati rappresentativi. Pertanto, l'insieme delle analisi mineralogiche, metallurgiche, chimiche e isotopiche, attraverso il confronto con i database esistenti per gli isotopi del piombo, i dati pubblicati in letteratura e il database sviluppato all’interno dell’ Alpine Archaeocopper Project (AAcP) ha consentito l'identificazione della provenienza del metallo. I risultati hanno mostrato che i lingotti sono fondamentalmente costituiti da rame e, solo in pochi casi, da bronzo; le concentrazioni degli elementi minori e in traccia dipendono dalla carica minerale e dal processo impiegato per l’estrazione e il raffinamento. Inoltre, le analisi hanno rivelato che le armi sono state alligate intenzionalmente con lo scopo di ottenere un bronzo malleabile. La grande quantità di dati raccolti in questo studio ha portato alla distinzione di due cariche minerali utilizzate in ambienti metallurgici ben definite; infatti, i depositi caratterizzati da calcopirite sono stati sfruttati in maniera esclusiva durante Bronzo Recente-Finale per la produzione dei lingotti e degli oggetti dei depositi di Cervignano e Muscoli, mentre sporadiche testimonianze sono documentate nei periodi successivi. In questo scenario, in Castions di Strada (BF) si riscontra un cambiamento nella carica minerale e, conseguentemente, viene attestata la ripresa nell’uso di minerali fahlerz; inoltre, questa inversione di tendenza è stata confermata anche dai risultati riguardanti i materiali scoperti a Porpetto che hanno mostrato una spiccata affinità chimica con i lingotti sloveni. Gli studi di provenienza hanno evidenziato che dal Bronzo Medio al Bronzo Finale evoluto le Alpi Sud-orientali erano costantemente sfruttate per l’estrazione di rame da calcopirite, con l’intento di ottenere lingotti di rame puro e, successivamente, oggetti di prestigio come armi e strumenti. Solo nel Bronzo Finale, si assiste all’impiego di il rame estratto da nuovi depositi minerali (Austria, Europa centrale e Bulgaria), la cui circolazione è stata dimostrata in Friuli Venezia Giulia. Inoltre, nel Bronzo Recente la circolazione del bronzo è testimoniata dal ritrovamento di piccoli lingotti a barra che, nel Bronzo Finale hanno assunto la forma ben nota dei pani a piccone, come evidenziato in Galleriano. Tuttavia, la particolare composizione dei pani a piccone di Porpetto ha dimostrato che tale lingotto circolava con forma standard indipendentemente dalla composizione della lega, probabilmente in sfere commerciali ben distinte.
Röbbert, Yvonne [Verfasser]. "Mobilization and isotope fractionation of uranium, copper and iron in the environment - implications for (bio)remediation of contaminated sites and mine tailings / Yvonne Röbbert." Hannover : Gottfried Wilhelm Leibniz Universität, 2021. http://d-nb.info/1238222722/34.
Full textRyberg, Per. "Concerted or Stepwise? : β-Elimination, Nucleophilic Substitution, Copper Catalysed Aziridination and Ruthenium Catalysed Transfer Hydrogenation Studied by Kinetic Isotope Effects and Linear Free-Energy Relationships." Doctoral thesis, Uppsala universitet, Avdelningen för organisk kemi, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-2008.
Full textThibon, Fanny. "Chimie des océans au Paléoprotérozoïque." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEN008/document.
Full textThe present-day oxidizing conditions at Earth's surface are due to the high oxygen content of the atmosphere. However, oxygen was not always stable in the terrestrial atmosphere. Two distinct periods during which oxygen increased in a step-like manner were required to reach the current atmospheric oxygen level. The first, at about 2.4 Ga, is known as the Great Oxidation Event (GOE) and is at the core of this Ph.D. thesis. The other, occurring almost two billion years later, is called the Neo-Proterozoic Oxidation Event (NOE). The GOE likely is the result of the beginning widespread emergence of large continental expanses whose subsequent erosion gradually released phosphate into the ocean. Phosphate, a nutrient essential to organic production, in turn allowed the explosion of oxygenated photosynthesis. The GOE and NOE coincide with two major changes in the history of life. Shortly after the GOE, eukaryotes appeared, while the NOE corresponds to the appearance of metazoans and the Cambrian explosion. A better grasp of the GOE hence may have important implications for the understanding of the origin and evolution of life, which is thought to have been mainly marine at this stage in Earth history. The only records of the oxygen level during these ancient times are found in terrestrial sedimentary rocks. To understand how oxygenation of the atmosphere relates to marine life, we must first understand how the ocean was connected to the atmosphere during the GOE and how the GOE affected life-dependent ocean biogeochemical cycles. To this end we focused on banded iron formations (BIF). The chemistry of these sedimentary marine rocks directly reflects the chemistry of the contemporary ocean. Deriving quantitatively the composition of the ocean from a hydrogenous sediment is a challenge almost impossible to meet, even for the modern ocean. This is why we instead determined the residence time of redox-sensitive elements (in this case sulfur, iron, and copper) in the pre-GOE ocean. We specifically targeted the periods of isotopic fluctuations in these elements as recorded in BIF cores. The lower limit of the spectrum provides the residence time of these elements in seawater, hence giving a robust indication of their contents in the pre-GOE ocean. We sampled early Proterozoic BIF near the Archean-Proterozoic boundary in Transvaal (South Africa) and Hamersley (Australia), as well as Archean BIF from Nuvvuagittuq (Canada), though the latter were not analyzed during this thesis due to shortage of time
MIYANO, ROSANA S. L. "Estudos de compactação de pó de níquel para produção de alvos de irradiação." reponame:Repositório Institucional do IPEN, 2014. http://repositorio.ipen.br:8080/xmlui/handle/123456789/25190.
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Dissertação (Mestrado em Tecnologia Nuclear)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
Phukphatthanachai, Pranee. "Development and Application of IDMS Based Procedure for total Sulphur in Copper Metals and Its Alloys." Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/19851.
Full textSulphur quantification in copper and other pure metals in the past revealed a lack of SI-traceability and also showed inconsistent results, when different methods are compared. Therefore, a reference procedure is required to enable SI-traceable measurement results accompanied by a sound uncertainty budget. In this study, such a procedure was developed for the quantification of total sulphur in copper using inductively coupled plasma-isotope dilution mass spectrometry (ICP-IDMS). For solving these problems ion exchange chromatography was applied, and a sulphur-matrix separation procedure was developed. This procedure was combined with ICP-IDMS to solve difficulties with the calibration and to realize metrological concepts. An application of the IDMS procedure was realized by using the measurement results of specific copper samples values for calibrating glow discharge mass spectrometry (GDMS) and laser ablation ICP-MS (LA-ICP-MS). Both techniques are considered routine techniques. Thus, they could provide reliable results which are traceable to the SI. Additionally, a procedure based on LA-ICP-IDMS was developed to significantly reduce the sample preparation step of ICP-IDMS with sulphur-matrix separation. This procedure is less laborious and the measurement results are still SI traceable and offer a comparatively high accuracy for LA-ICP-MS. Key for this development was the innovative application of polyethylene frits as support material for the dissolved sample. Thus, the quantification of sulphur in copper samples by LA-ICP-IDMS could be realized. The essential parameters are investigated such as the absorption efficiency of the frit and matrix effects. The developed procedure was fully validated by means of the ICP-IDMS results.
Thapalia, Anita. "Zinc and copper isotopes as tracers of anthropogenic contamination in a sediment core from an urban lake." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2009. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
Full textBarra-Pantoja, Luis Fernando. "A Re-Os Study of Sulfides from the Bagdad Porphyry Cu-Mo Deposit, Northern Arizona, USA." Thesis, The University of Arizona, 2001. http://hdl.handle.net/10150/249252.
Full textLavigne, André. "Oxydations cupro-catalysees des amines aliphatiques : etudes mecanistiques et applications synthetiques." Paris 6, 1987. http://www.theses.fr/1987PA066470.
Full textPetit, Jérôme. "Nouveaux outils en sciences de l'environnement: géochimie isotopique du Cu-Zn et spéciation des éléments en trace métalliques par titrage acidimétrique :développement et applications aux phases particulaires de l'estuaire de l'Escaut, aux émissions atmosphériques et aux sols contaminés d'Angleur/Prayon." Doctoral thesis, Universite Libre de Bruxelles, 2009. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210231.
Full textSi la géochimie isotopique du Cu et du Zn a le potentiel de distinguer différentes sources de pollution, l’évaluation des risques liés à ces pollutions doit tenir compte des formes chimiques des ETM, typiquement mises en évidences par les méthodes d’extraction sélectives (séquentielles, dont le protocole BCR). La méthode alternative proposée pour l’étude de la spéciation, plus versatile (capable de mettre en évidence des phases non prédéfinies et applicable à une variété de matrices plus large) est capable de surmonter plusieurs limitations (dont les problèmes de sélectivité liées au mauvais contrôle de l’acidité du milieu réactionnel) caractéristiques des méthodes traditionnelles. Appliquée à des sédiments marins/estuariens et des sols, la méthode de titrage acidimétrique s’est révélée capable de quantifier les proportions relatives des phases acido-solubles (principal problème des méthodes d’extraction sélectives), ce qui permet d’établir univoquement la spéciation des éléments qui leurs sont associés, d’évaluer la réactivité des ETM vis-à-vis du pH, mais aussi d’évaluer la sélectivité des protocoles d’extraction séquentielle « BCR » et « Tessier ». La méthode de titrage acidimétrique apporte également des informations importantes sur la géochimie des éléments majeurs dans l’estuaire de l’Escaut et met en évidence les particularités minéralogiques des sols pollués en comparaison aux sédiments.
Les études de cas démontrent que ces nouvelles techniques ont des applications dans le domaine de la géochimie de l’environnement, mais peuvent également être vouées, sur le moyen/long terme à une utilisation sortant du cadre des sciences exactes. En effet, l’identification/discrimination des sources de pollutions et l’évaluation des risques de remobilisation des polluants métalliques font partie des nombreuses questions posées par la société aux scientifiques de l’environnement.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
Enrico, Michael Paul. "Ballistic excitation scattering processes in superfluid '3He-B and spin-lattice relaxation in copper down to 7#mu#K." Thesis, Lancaster University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261014.
Full textGirardi, James Daniel. "Comparison of Mesozoic Magmatic Evolution and Iron Oxide (-Copper-Gold) (`IOCG') Mineralization, Central Andes and Western North America." Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/319881.
Full textToubhans, Benoit. "Bio-géochimie du cancer : Utilisation des nanoparticules de sélénium dans le traitement et des isotopes du cuivre dans la détection des cancers ovariens." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALU017.
Full textOvarian cancer is the seventh most common cancer in women with five-year survival rates of less than 45%, and only 20% of cases are detected at early stages of the disease. Major challenges still exist to treat this lethal disease.The development of new drugs that target better cancer cells and reduce side effects is highly needed. Selenium at high doses has been shown to act as a cytotoxic agent, with potential applications in cancer treatment. However, clinical trials have failed to show any chemotherapeutic value of selenium at safe and tolerated doses (<90 g/day). To enable the successful exploitation of selenium for cancer treatment, I evaluated inorganic selenium nanoparticles (SeNP), and found them effective in inhibiting ovarian cancer cell growth. In both SKOV-3 and OVCAR-3 ovarian cancer cell lines SeNP treatment resulted in significant cytotoxicity. The two cell types displayed contrasting nanomechanical responses to SeNPs, with decreased surface roughness and membrane stiffness characteristic of OVCAR-3 cell responses. In SKOV-3, cell membrane surface roughness and stiffness increased, both are properties associated with decreased metastatic potential. Very excitingly I made the novel discovery that SeNPs dramatically increase histone methylation at three histone marks, namely H3K4, H3K27 and H3K9. This effect was partially blocked by pharmacological agents that blocked histone methyltransferase (HMT) function. Gene expression profiling of SeNP treated cells demonstrated that Se caused changes in the expression of HMTs suggesting one mechanism for its ability to alter histone methylation. Further interrogation of RNA seq data showed the SeNPs impact on the expression of genes linked to hallmarks of cancer such as DNA repair activation, ROS response, extracellular matrix organization. The beneficial effects of SeNPs on ovarian cancer cell death appear to be cell type dependent, and due to their low in vivo toxicity, offer an exciting opportunity for future cancer treatment.Finally, following on from recent studies in breast and colorectal cancer patients revealing that measurement of circulating copper isotopes (63Cu/65Cu ratio) can be related to cancer development I investigated this in clinical ovarian cancer samples (blood and tissue). A significant decrease in copper isotopic ratios in the serum of cancer donors was observed demonstrating the potential effectiveness of 63Cu/65Cu for the blood-based detection of ovarian cancer
Jago, Christopher Paul. "Metal- and alteration-zoning, and hydrothermal flow paths at the moderately-tilted, silica-saturated Mt. Milligan copper-gold alkalic porphyry deposit." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/609.
Full textLomant, Susannah E. "Calculations of nuclear cross sections and astrophysical S-factors for reactions induced by protons and alpha particles on isotopes of copper." Virtual Press, 1999. http://liblink.bsu.edu/uhtbin/catkey/1137475.
Full textDepartment of Physics and Astronomy
Sauzéat, Lucie. "Vieillissement et maladies neurodégénératives : nouvelles contraintes apportées par la métallomique." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEN005/document.
Full textCharacterized by the progressive and irreversible decline of vital biological functions, ageing is a complex biological process that often comes with neurodegenerative disorders. In 2050, more than 1.5 billion elderly are expected in the world. Improve the quality of life of these ageing people is therefore a major challenge for our society. Still poorly known, the progressive degradation of the metallome is asscociated with ageing and neurodegenerative diseases development and is probably one of their causes. The objective of this study is to better characterize the metallome evolution in two animal models over time i.e. the mouse and the worm as well as in human affected by amyotrophic lateral sclerosis (ALS). To do this, we analyzed twenty trace and major elements as well as the isotopic compositions of copper (δ65Cu) and zinc (δ66Zn) of mouse organs, different strains of nematodes, and human cerebrospinal fluid (CSFs).The analysis of mouse organs shows that important chemical and isotopic changes develop in the body over time, each organ having its own elemental and isotopic signature. For example, we observe an increase of the Cu concentration in the brain associated with a decrease of the δ65Cu in the liver over time. Based on the analysis of metabolomic parameters and the use of isotopic mixings, we show that these variations may be explained by major physiological and metabolic dysfunctions, such as the deregulation of hepatic fluxes and/or the degradation of the blood-brain barrier with age. This suggests that the temporal analysis of the metallome could be used as a potential marker of the biological age.The analysis of nematodes revealed that long-lived animals differ from short-lived nematodes by an early-age decrease in their Cu isotopic composition and Cu concentration. The temporal monitoring of these biomarkers could therefore be used to detect premature ageing conditions.Finally, the analysis of CSFs of patients with amyotrophic lateral sclerosis (ALS), a severe neurodegenerative disease for which there is currently no reliable biomarker or treatment, shows that ALS patients have a higher δ65Cu compared to healthy subjects and Alzheimer’s disease patients. This feature, offering new perspectives to identify ALS-specific biomarkers, may be explained by the formation of toxic protein aggregates in the brain
Jaouen, Klervia. "Les isotopes des métaux de transition (Cu, Fe, Zn) au service de l'anthropologie." Phd thesis, Ecole normale supérieure de lyon - ENS LYON, 2012. http://tel.archives-ouvertes.fr/tel-00781645.
Full textvaz, Sidre Stelvio. "The stratigraphic and structural controls on copper-gold mineralization at Cassenha hill prospect, within the Archean to Paleoproterozoic Angolan shield, Congo craton, South Western Angola." Master's thesis, Faculty of Science, 2021. http://hdl.handle.net/11427/34008.
Full textWinter, Lawrence Stephen. "The genesis of ‘giant’ copper-zinc-gold-silver volcanogenic massive sulphide deposits at Tambogrande, Perú : age, tectonic setting, paleomorphology, lithogeochemistry, and radiogenic isotopes." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/773.
Full textBoehme-Terrana, Linae Marie. "Trace metals and stable isotopes as tracers of life history and trophic connections in estuarine-dependent fish from Tampa Bay, Florida." [Tampa, Fla.] : University of South Florida, 2007. http://purl.fcla.edu/usf/dc/et/SFE0002241.
Full textQi, Dongmei [Verfasser]. "Isotopic and elemental distribution of copper between Cu-bearing minerals and aqueous fluids : implications of an experimental study / Dongmei Qi." Hannover : Gottfried Wilhelm Leibniz Universität Hannover, 2019. http://d-nb.info/1176105213/34.
Full textPlumhoff, Alexandra [Verfasser], Thorsten [Gutachter] Schäfer, and Juraj [Gutachter] Majzlan. "Thermodynamic properties, crystal structures, phase relations and isotopic studies of selected copper oxysalts / Alexandra Plumhoff ; Gutachter: Thorsten Schäfer, Juraj Majzlan." Jena : Friedrich-Schiller-Universität Jena, 2020. http://d-nb.info/1223214656/34.
Full textBlotevogel, Simon. "Etude des transferts élémentaires et mécanismes biogéochimiques dans le continuum sol-plante-vin par l'utilisation de traceurs isotopiques et biochimiques." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30373/document.
Full textIn western Europe, soil is of primordial importance for wine making. Soil qualities are often discussed and an influence on wine flavor is frequently inferred. However, evidence for a role of soil chemistry on wine composition and taste is scarce, but mineral nutrition of grapevine plants is one possible way of influence. This thesis approaches the complex question of elemental cycling between soil and plant through the use of geochemical tracers in vineyard environments. A combination of traditional tracers such as elemental ratios and mass balances as well as innovative tools such as Cu isotope analysis and electron paramagnetic resonance (EPR) are used on different observation scales. The influence of soil type on wine elemental composition was investigated using over 200 wine samples from France, Germany, Italy and Spain. Results of chemical analysis were then statistically linked to environmental conditions. At this scale, elemental contents of wine vary depending on soil type (calcareous or not), meteorological conditions, and wine making practice. To determine which soil properties can influence the chemical composition of grapevine plants, two vineyard plots on contrasted soils in Soave (Italy) were examined. Soil forming mechanisms were studied along two catenas and subsequently linked to elemental composition of grapevine plants and biochemical markers of plant health. Even though soil morphology was different, complex soil forming processes led to similar geochemical properties of soils. Differences in plant chemical compositions between soil types are small compared to inter-individual and inter-annual variability. However the use of Sr isotopic ratios allows the determination of the pedological origin of plants. In a next step, the fate of Cu pesticides in vineyard soils was studied. Cu-based pesticides have been used for almost 150 years in European vineyards and Cu accumulates in soils, so that the fate of Cu and its ecotoxicological implications are of growing importance. Therefore, Cu mobility in vineyard soils and transfer to grapevine plants were investigated using stable Cu-isotope ratios and EPR-measurements. Isotope ratios of Cu-based fungicides vary largely between products, covering Cu isotope ratios in soils reported in literature and thus making source tracing impossible. However, Cu isotope ratios are useful for tracing biogeochemical mechanisms of Cu transport in soils. The vertical transport of Cu in different soil types was investigated in the Soave vineyard using a combination of mass balance calculations, kinetic extractions and δ65Cu-isotope ratios. Results suggest that Cu can be transported to depth even in carbonated environments. Besides it is shown that heavy organic-bound Cu is lost from carbonated soil columns likely caused by dissolution of Cu carbonates by organic matter. [...]
Gillet, Raphaël. "Synthèse et caractérisation de bispidines, chélatants du 64Cu, en vue d’applications pour la tomographie à émission de positrons." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAF058/document.
Full textThis PhD work aimed at developing new bispidine-based copper(II) chelating agents for applications in Positron Emission Tomography (PET). On one hand, 64Cu is a metallic radioisotope which possesses interesting properties for PET imaging and on the other hand, bispidines have a pre-organized and rigid structure. This property makes them good chelating agents for numerous transition metals, particularly copper(II). This work presents the development of a new bispidine-based ligand having a phosphonate pendant arm as well as the development of bispidines allowing the synthesis of new chelating agents for copper(II). The physico-chemical properties of the phosphonated bispidine were thoroughly studied by different techniques, showing that it would be adequat for PET applications. Radiolabeling experiments were also done in the presence of 64Cu for various bispidines and show the high potential of bispidine ligands for the complexation of 64Cu. Finally, several functionalization strategies were studied in order to get bifunctional chelates based on the phosphonated bispidines. This study proved the possibility to develop two bifunctional bispidines based on the phosphonated one and also it allowed us to develop two bifunctional bispidines as synthon for the synthesis of new families of bifunctional bispidines
Pestilho, Andre Luiz Silva 1985. "Sistemática de isótopos estáveis aplicada à caracterização da evolução dos paleo-sistemas hidrotermais associados aos depósitos cupríferos Alvo Bacada e Alvo Castanha, Província Mineral do Carajás, PA." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/286851.
Full textDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências
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Resumo: Localizados na porção norte da Província Mineral de Carajás, a uma distância de cerca de 8 km do depósito de óxido de ferro-cobre-ouro de Sossego, estão os depósitos de cobre Alvo Bacaba e Alvo Castanha. Esses depósitos encontram-se ao longo de uma zona de cizalhamento regional de cerca de 60 km de extensão, no limite entre o Supergrupo Itacaúnas e seu embasamento representados principalmente pelos migmatitos do complexo Xingu. O Alvo Bacaba é hospedado pelo granito Serra Dourada e pelo tonalito Bacaba, enquanto o Alvo Castanha é Ambos os depósitos exibem amplas zonas de alteração hidrotermal que compreendem quase que respectivamente a albitização, a escapolitização, a formação de óxidos de ferro, a alteração sódico-cálcica, a alteração potássica, a formação de turmalina, a sericitização, a cloritização, a epidotização e a carbonatização, embora estes depósitos mostrem diferenças, como a alteração sódico-cálcica que apesar de ser bem desenvolvida no Alvo Castanha, é quase inexistente no Alvo Bacaba, onde apenas ocorre como alteração nos gabros. Também o Alvo Bacaba possui uma associação de minerais distintas, composta por calcopirita±pirita±bornita, enquanto o Alvo Castanha exibe a associação calcopirita±pirrotita±pirita. Informações sobre evolução paragenética e dados de isótopos estáveis indicam que os depósitos Alvo Bacaba e Alvo Castanha evoluíram durante progressivo resfriamento. Entretanto, esta redução com relação à evolução paragenética foi maior no Alvo Bacaba do que no Alvo Castanha, e a fugacidade de oxigênio foi mantida alta no Alvo Bacaba. A temperatura de deposição do minério estimada para o Alvo Bacaba pode ter ocorrido entre 220 °C e 410 °C, enquanto no Alvo Castanha esta teria ocorrido entre 350 °C e 420 °C. A evolução isotópica do Alvo Bacaba é similar àquela caracterizada para o depósito de Sossego, com uma redução acentuada da temperatura acompanhada por um decréscimo no valor de ?18O e acréscimo no valor de ?D e evidências de misturas de fluido juvenil e de fonte não magmática. Já para o Alvo Castanha, as composições isotópicas dos fluidos hidrotermais indicam a predominância de uma fonte magmática. Estas características e similaridades com aquelas de Sossego podem apontar para uma contribuição de águas magmáticas e oceânicas no sistema hidrotermal que originou todos estes depósitos
Abstract: The Alvo Bacaba and Alvo Castanha copper deposits are located at the northern part of the Carajás Mineral Province, at a distant radius of about 8 km from the Sossego iron oxide-copper-gold deposit. These deposits occur along a regional shear zone 60 km wide, in the limit between the Itacaiúnas Supergroup and its basement represented mainly by migmatites of the Xingu Complex. Both deposits exhibits widespread hydrothermal alteration zones comprising albitization, scapolitization, iron oxide formation, sodic-calcic alteration, potassic alteration, tourmaline formation, sericitization, epidotization and carbonatization, although these two deposits show differences like sodic-calcic alteration, which is well developed in Alvo Castanha, but it is almost inexistant in Alvo Bacaba, being present only in its altered gabbros. Also the Alvo Bacaba shows ore minerals association essencialy composed by chalcopyrite±pyrite±bornite while the Alvo Castanha shows the association of chalcopyrite±pyrrhotite±pyrite. Paragenesis and stable isotope data indicate that the Alvo Bacaba and Alvo Castanha deposits have evolved with temperature decrease. However, the temperature drop in relation to the hydrothermal alteration succession was greater in Alvo Bacaba than the Alvo Castanha, and the oxygen fugacity was kept higher at Alvo Bacaba. The estimated temperature for ore deposition in the Alvo Bacaba was between 220 °C and 410 °C, while the Alvo Castanha it would have occurred between 350 °C and 420 °C. The isotopic evolution of the Alvo Bacaba is similar to that characterized for the Sossego deposit, with a steep temperature reduction accompanied by decrease of ?18O and increase of ?D values and fluid mixing evidences. In the Alvo Castanha, isotopic compositions of the hydrothermal fluids indicate predominance of magmatic sources. These characteristics and its similarities with those of the Sossego deposit could point to a contribution of magmatic and ocean waters in the hydrothermal system that originated all deposits
Mestrado
Geologia e Recursos Naturais
Mestre em Geociências
Goy, Julie. "La métallurgie du cuivre à l'âge du Fer en péninsule d'Oman : organisations et caractéristiques techniques." Thesis, Paris 1, 2019. http://www.theses.fr/2019PA01H063.
Full textThe Oman Peninsula is a geo-cultural entity organized around the al-Hajjar mountains, which are extremely rich in copper ores. This metal was probably exploited since the Hafit period (3000 - 2500 BC) and the metal produced will become a trading material with Mesopotamia during the Umm an-Nar period (2500 - 1900 BC). During the Iron Age (1350 - 300 B.C.), these exchanges became more blurred, but copper production did not decrease. The reduction and metalworking sites of the Oman Peninsula are extremely massive and operate with complex management and organization. Moreover, this metal is not competitive, as iron was only produced at the end of the Iron Age and bronze is relatively under-represented in the metallic corpus. Our study attempted to identify the processes implemented by metallurgists using a methodology that combines archaeometallurgical prospecting and physico-chemical analysis of production remains (slag, ingots and finished objects). These objects were found in various contexts : settlements, hiding places or metallurgical workshops. They are mainly weapons, bracelets, bowls and snake figurines, an animal to which the local populations seemed to devote an exclusive cult. Chemical analysis attest a local production, using ore from the al-Hajjar mountains. However, it appears that the practice of recycling objects actively contributes to the supply of copper to the population. The resulting metal is chemically highly mixed and appears to have been used in the manufacture of many objects, regardless of type or use. Despite the absence of a writing system, archaeological remains of the Iron Age populations attest to a complex social organization, in which copper seems to have played an important role, contributing to the development of a strong local identity
Rinaldi, Luís Felipe. "Eficiência de uso de 15N-ureia tratada com inibidores de urease em associação com substâncias húmicas pela cultura do milho." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/11/11140/tde-28062018-155919/.
Full textUrea (UR) is the most widely applied nitrogen (N) fertilizer in Brazilian agriculture. However, UR is more prone to ammonia (NH3) volatilization losses than other N sources when surface-applied. One alternative to improve nitrogen use efficiency (NUE) of surface-applied UR is through application of urease inhibitors as coating materials of UR. The association of these composts with humic substances (HS) as UR coating materials may also improve nutrient recovery by plants. The aim of this study was to evaluate the efficiency of urease inhibitors, associated or not with HS, as coating materials of UR as new top-dress N sources for maize. A greenhouse pot trial was carried out over 62 days with maize (Zea mays L.), in a completely randomized block design, with three replicates in a full factorial design, with UR coated with three urease inhibitors (0,40% B + 0,15% Cu; 0,64% B; NBPT) and one additional treatment without inhibitor, three doses of HS (0, 0.6, and 1.2%), and one control treatment. All treatments imposed had CO(15NH2)2 as N source, application rate of 180 mg kg-1of N, and side-dressing application at the V4 maize growth stage. Maize plants were assessed at V8 and VT growth stages, at 52 and 62 days after sowing, respectively, when it was evaluated: above and below-ground plant dry matter weight; leaf area; root morphological traits (length, surface area, and volume); and fertilizer use efficiency by the 15N balance method. In addition, semi-open static collectors with foam discs previously soaked in H3PO4- were used to quantify comparatively the NH3 volatilized from all treatments. Although the addition of a higher dose of boric acid on UR (0,64% B) promoted lower ammonia losses by volatilization in comparison to 0,40 % B + 0,15 % Cu, it did not result in higher NUE by maize in VT, which occurred at V8. In both growth stages, NBPT presented the best performance as urease inhibitor in the absence of HS. The application of HS did not increase NUE by maize in V8 and VT when associated with 0,40% B + 0,15% Cu, 0,64% B or even conventional UR. However, when added in conjunction with NBPT, it increased ammonia volatilization and reduced NUE in VT which may have occurred due to the high pH of the HS (8.5-9) and low buffering capacity. Moreover, the application of conventional UR or UR treated with HS and urease inhibitors did not increase maize growth rate or shoot/root dry matter weight in comparison to the control treatment at both growth stages. Likewise, there was no major significant differences between treatments on root morphological traits (length, surface area, and volume) at both growth stages assessed. The lack of sizable outcome differences between treatments could be explained by the application of a single N dose, the short period of time between the side-dressing application and assessment of maize plants, and to the surface-application of the HS and method of irrigation which prevented HS to have full contact with maize roots. Furthermore, HS application rate may have been too low to be effective.
Lowczak, C. R. "Copper isotope method development for determining the source of mineralised provinces." Thesis, 2019. https://hdl.handle.net/2440/136974.
Full textMany isotope proxies have been applied to study the prosperous iron oxide copper gold (IOCG) province in the eastern Gawler Craton (E.G.C) and Au mineralised region of the cental Gawler Craton (C.G.C), in Southern Australia. Yet, copper isotope proxies- an indicator for low temperature fluid flow and sulfide mineralisation- have yet to be applied to the region. In this study, purification techniques using automatic column chromatography were demonstrated during separation of Cu from matrix elements. Cu isotopes – 65Cu & 63Cu – were used to understand the extent of mantle input and mantle metasomatism, potentially responsible for the Cu in IOCG mineralisation. Eleven samples were gathered. Three mafic enclaves and four intrusives from the Central Gawler Gold Province and four intrusives from the eastern Gawler IOCG province. Separation using automatic column chromatography proved challenging, with matrix elements abundant throughout the purified fractions (Co, Ti, Fe, Mg, Na), due to poor separation. Ti proved to a major interference during isotopic analysis using a Multicollector-ICP-MS, positively offsetting values. E.C.G samples showed the most positively fractionated δ65Cu values (+0.69 ± 0.024‰ to +1.422 ± 0.077‰). Enclaves from the C.G.C showed the most negatively fractionated δ65Cu values (-0.053 ± 0.023‰ to -0.897 ± 0.006‰), while intrusives from this region showed more positive δ65Cu values (+0.084±0.23‰ to +0.397±0.011‰). All samples showed a lack of hydrothermal alteration. Magmatic sulphide-containing E.G.C samples had the most positive δ65Cu values; which cannot be explained by current understanding of Cu isotope fractionation during sulfide saturation. This trend may instead be attributed to a heterogeneous sub-continental lithospheric mantle (SCLM) source. In contrast the negative δ65Cu values of mafic enclaves is possibly caused by assimilation of S-type granitic crust and/or possibly due to a heterogeneous SCLM source.
Thesis (B.Sc.(Hons)) -- University of Adelaide, School of Physical Sciences, 2019
Ignacio, AM. "Supergene mineralisation of the Boyongan porphyry copper-gold deposit, Surigao del Norte, Philippines." Thesis, 2006. https://eprints.utas.edu.au/23741/1/Ignacio_Boyongan_MSc%20Thesis.pdf.
Full textShackman, Leah Caitlin. "Isotope effects in gas-surface interactions: quantum-state resolved studies of D₂ scattering from Cu(100) and Pd(111)." Thesis, 2004. http://hdl.handle.net/2152/2193.
Full textShackman, Leah Caitlin Sitz Greg Orman. "Isotope effects in gas-surface interactions quantum-state resolved studies of D₂ scattering from Cu(100) and Pd(111) /." 2004. http://repositories.lib.utexas.edu/bitstream/handle/2152/2193/shackmanlc042.pdf.
Full textDurali-Müller, Soodabeh [Verfasser]. "Roman lead and copper mining in Germany : their origin and development through time, deduced from lead and copper isotope provenance studies / von Soodabeh Durali-Müller." 2006. http://d-nb.info/979507677/34.
Full textJohnson, James Patrick. "The geochronology and radiogenic isotope systematics of the Olympic Dam copper-uranium-gold-silver deposit, South Australia." Phd thesis, 1993. http://hdl.handle.net/1885/10918.
Full textBigalke, Moritz [Verfasser]. "Copper and zinc stable isotope ratios as tracers of biogeochemical processes, sources and transport of Cu and Zn in soils / Moritz Bigalke." 2010. http://d-nb.info/1007569638/34.
Full textPrice, Jason Brian. "I: Normal Faulting on the Austroalpine ‘Overthrust’ Constrained by Thermochronometry and Kinematic Analysis, Central Alps, Graubünden Region, Switzerland. II: Clumped Isotope Thermometry of Carbonate Phases Associated with the Copper Deposits of Kennecott, Alaska." Thesis, 2017. https://thesis.library.caltech.edu/10171/7/Price_PhD_20170527.v2.pdf.
Full textI. A compilation of 362 cooling ages, including 52 newly reported in this study, from nine thermochronometric systems, 40K/39Ar amphibole, 40K/39Ar white mica, 87Rb/86Sr white mica, 40K/39Ar biotite, 87Rb/86Sr biotite, zircon and apatite fission track, zircon and apatite (U-Th)/He, indicate that the base of the Austroalpine allochthonous ‘orogenic lid’ was not in full thermal equilibrium with its Penninic substrate until at least the middle Oligocene, approximately 29-28 Ma, to allowably as late as the early Miocene, ca. 18 Ma. There is about a factor-of-five difference in cooling rates between the hanging wall (ca. 4°C/m.y.) and footwall (ca. 20°C/m.y.) during this period. In addition, there are demonstrably higher metamorphic grades, including blueschist- and eclogite-facies, in the Pennine footwall compared to lower greenschist-facies in the Austroalpine hanging wall. Together these two facts demonstrate that hot, high-pressure Penninic nappes were forced upward against the cold, low-pressure overriding Austroalpine plate in a very short time window of approximately 7-10 m.y. between the time of peak metamorphism during the Eocene and the time of thermal equilibration with the overriding plate during the Oligo-Miocene. The most likely mechanism to produce such a cold-on-hot juxtaposition is a normal fault, and therefore, we conclude that an important period of nappe emplacement in the Central Swiss Alps occurred concurrently with orogen-perpendicular normal fault motion at the base of the Austroalpine allochthon persisting well into the Oligocene and possibly into the early Miocene, post-dating the 32-30 Ma age of the Bergell intrusion.
Mesoscopic structural measurements made at the top and bottom of the Pennine zone in eastern Switzerland indicate multiple, spatially heterogeneous directions of movement. At the top, in the Oberhalbstein Valley, movement directions vary from dominantly top-east to top-south-southeast a very minor top-north component within Pennine rocks of the Martegnas shear zone and no preferred movement direction within the Austroalpine hanging wall. Near Piz Toissa, a minimum of two kilometers of nearby structural section in the Err and Platta nappes have been faulted out. At the bottom of the Pennine zone in Val Lumnezia and the Chur Rhein Valley at Trimmis, we observe top-northwest, top-north, and top-northeast movements. In Val Lumnezia, the Sub-Penninic Scopi zone (Gotthard cover rocks) shows movement in a top-northwest direction; the superjacent Peidener imbricate fault zone, a relatively thin (ca. 50 to 100 m thick) structural zone consisting of Scopi zone lithologies, shows movement in a northeasterly direction; above that, the basal Penninic Bündnerschiefer shows no dominant movement direction. To the east, in the Chur Rhine Valley, movement is well defined as exclusively top-north. Therefore, movement directions in the lower Bündnerschiefer are broadly top-north but heterogeneous in direction along strike between Val Lumnezia and Chur Rhein Valley, and, as first suggested by Weh and Frotizheim (2001), it may be erroneous to regard the basal Pennine thrust as a simple through-going structure. In Val Lumnezia, the Scopi-Peidener-Pennine nappes resemble a “jelly sandwich” in which the thick Pennine mass utilized the Peidener zone to move in an oblique sinistral-normal slip sense past the southeast-dipping allochthonous Scopi zone and its east-dipping Gotthard “massif” substrate. If the Peidener zone continues northeastward beneath alluvial cover of the Chur Rhein Valley, it may serve as a late, NE-directed shear zone that separates the Pennine nappes from European units. If so, it would explain the apparent truncation and progressive omission of allochthonous elements of European affinity along the zone from southwest to northeast beneath alluvium of the Chur Rhein Valley. We therefore infer that the direct juxtaposition of Penninic units to the east with the Helvetic autochthon to the west at the latitude of Trimmis records an episode of top-northeast, orogen-parallel strike-slip and extensional movement.
Zircon (U-Th)/He (ZHe) cooling ages from the Oberhalbstein Valley indicate that the Austroalpine-Pennine contact was still active at ca. 27 Ma, and that the Martegnas shear zone was active, in part, between ca. 27 and 24 Ma. It is likely that the Piz Toissa klippe formed around this time during the late Oligocene. The pattern of much younger ZHe ages at the bottom of the Pennine zone is independent of any nappe boundaries, including the Peidener imbricate fault zone, but is consistent with the rise of the Aar massif during the Miocene. Tectonic movements, as recorded by the mesostructure in the Austroalpine, Penninic, and Sub-Penninic domains, and local ZHe cooling ages generally support the conclusion drawn strictly from cooling ages that the Pennine zone was emplaced en masse as a coherent ‘piston’ or ‘mega-pip’ during Oligocene to early Miocene time (approximately 29 to 18 Ma), well after juxtaposition of Apulia with cratonic Europe (continent-continent collision) and during the development of Alpine topography and the peripheral basins (viz. Molasse and Lombardi). Additional top-north movement and late uplift and flexure of the nappe stack, along with the Aar massif, occurred primarily in middle to upper Miocene time, following the post-collisional structural interposition of the Pennine zone between Europe and Apulia.
II. Nine carbonate phases at Kennecott, Alaska were measured for their clumped isotope (∆47) equilibration temperatures. The total range for carbonate temperatures spans 38-164°C. Premineral phases are relatively cool (43-71°C); synmineral phases are relatively warm (89-157°C); late postmineral phases are the most cool (38-59°C) but overlap some premineral phases. Zebra dolomite precipitated in the range 130-163°C. Dedolomite, a hallmark alteration feature of the mineralizing fluids, falls into a narrow range of 98-109°C, consistent with the stability field for the low-temperature chalcocite polymorph. Except for one sample, none of the synmineral calcites crystallized within the stability field of djurleite, a volumetrically significant component of the main-stage ore, which suggests that intergrown djurleite may have been a somewhat later recrystallization product of chalcocite rather than a coeval phase.
Calculated compositions for δ18Owater vary from -4.2 to +11.0‰. The most depleted water precipitated hydrothermal baroque dolomite, whereas the most enriched water was associated with recrystallized limestone wallrock on the periphery of the orebody. Waters that precipitated calcite+copper vary from -1.1 to +9.3‰.
Intriguingly, rhythmic layering in zebra dolomite can be resolved in ∆47 space, and preliminary data indicate that the coarser-grained baroque dolomite bands precipitated at temperatures 5-10°C cooler than the surrounding, finer-grained dolomite wall rock bands.
The calculated values of δ18Owater support a genetic model that invokes redox changes associated with fluid mixing as the likely mechanism responsible for copper deposition. In this model a sulfidic, basinal fluid having δ18O similar to seawater mixes with a cuprous fluid having heavier δ18O (5 to 8‰) which was derived from the Nikolai Greenstone during prehnite-pumpellyite-facies metamorphism.